(a) Field of the Invention
The present invention relates to an exhaust system. More particularly, the present invention relates to an exhaust system reducing interference between exhaust gases.
(b) Description
Generally, a vehicle engine includes an exhaust system to discharge exhaust gases out of the vehicle.
A vehicle engine has a cylinder bank including a predetermined number of cylinders. An engine having cylinders disposed in a V-shape is called a V-shape engine.
If the bank includes four cylinders, the engine is called a V-8 type engine.
FIG. 1 shows an exhaust manifold of an exhaust system according to the prior art. Specifically, FIG. 1 shows an exhaust manifold mounted to a cylinder bank of a V-8 type engine.
FIG. 2 shows a V-8 type cylinder bank that is generally connected to an exhaust system. As shown in FIG. 2, the V-8 type engine includes two cylinder banks 201 and 202, and combustions in the four cylinders included in one of the cylinder banks 201 occur sequentially in the order of the numbers shown in FIG. 2.
Generally, the exhaust manifold shown in FIG. 1 is called a 4-1 type exhaust manifold.
In the 4-1 type exhaust manifold, a first exhaust gas runner 101 is connected to a second exhaust gas runner 103, and the second exhaust gas runner 103 is connected to a main exhaust gas runner 105.
Therefore, the exhaust gas is discharged out of a vehicle by sequentially passing the first, second, and main exhaust gas runners 101, 103, and 105.
While this type of manifold has a simple structure, it gives rise to a problem that overall performance of the engine can be reduced by gas interference between the runners.
Alternatively, a 4-2-1 type exhaust manifold has been developed. In this type of exhaust manifold, two of the four first exhaust gas runners are connected to one second exhaust gas runner, and two of such second exhaust gas runners can be disposed.
The 4-2-1 type exhaust manifold, however, has a drawback that it is hard to be mounted on a V-8 type engine because the angle between the two banks of the V-8 type engine is 90°. As a result, the manufacture is more difficult and the manufacturing cost is higher.
An additional drawback is increased heat release caused by increased area of the exhaust manifold.
There is thus a need for an improved exhaust system that can prevent a gas interference with simple scheme and reduce the amount of heat release.
The information disclosed in this Background of the Invention section is only for enhancement of understanding of the background of the invention and should not be taken as an acknowledgement or any form of suggestion that this information forms the prior art that is already known to a person skilled in the art.